Direct composite veneers versus etched porcelain laminate veneers

It would appear that over the years, the inherent weakness in composite veneering has been the composite itself. The etched porcelain restoration offers the advantages of increased strength, color, stability, and biocompatibility for a veneering material using composite merely as a luting agent. With the ongoing development of porcelain material, it is possible that the etched porcelain restoration will all but replace direct bonding in most clinical situations.     

Shear bond strengths of resin luting cements to laboratory-made composite resin veneers.

Retention problems have been reported with the clinical use of indirect microfilled resin veneers. This study used 24-hour shear tests to assess the bond strengths of such a resin veneer compared with other veneer types. The effect of different resin luting cements and resin veneer surface treatments were analyzed to elucidate factors by which retention could be increased. The six resin luting systems investigated showed a range of bond values. Debonding occurred primarily at the veneer/cement interface. G-Cera material produced the weakest bonds to Isosit-N resin. Surface treatment of Isosit-N veneers resulted in bond strength changes. Sandblasting reduced the force required for bond failure; Special Bond resin increased it slightly. Improving retention of prefabricated resin veneers proved difficult. Etched hybrid resin veneers delivered higher bond strengths than micro-filled resin veneers but not significantly. Etched porcelain veneers, however, provided consistently the strongest bond strengths with cohesive, as opposed to adhesive, bond failure.     

Direct composite resin inlay

Posterior composite resin restorations have several physical limitations. Polymerization shrinkage during curing and resistance to wear are two factors that can be alleviated by a composite resin inlay. Curing the restoration extraorally in a heat-and-light curing unit and cementing the restoration with a composite resin cement reduces the deleterious effects of polymerization shrinkage and increases wear resistance of the material. A method to make a direct composite resin inlay is detailed.     

复合树脂直接粘接修复Ⅳ.前牙直接粘接修复

前牙对人的发音和容貌有着重要影响,因此,前牙缺损修复将修复材料的色泽和质地等美学特性作为首要考虑因素,而将其强度和耐磨度置于第二位.     

复合树脂直接粘接修复Ⅴ.后牙直接粘接修复

后牙承担着较大的咀嚼咬合力,修复后牙龋坏或牙体缺损时,要均衡考虑材料的机械强度和耐磨性.银汞合金充填修复术操作简便,材料的机械性能好,被广泛应用于后牙龋损修复已有百余年,取得了良好的临床效果,但存在牺牲部分正常牙体组织以获得固位和颜色不符合美观要求等缺点.20世纪70年代以来,复合树脂开始应用于牙体缺损修复,但多用于前牙区对美学要求高的病例.早期由于粘接系统和复合树脂性能的不足,临床上出现继发龋或粘接失败的病例很多,加之耐磨性差,较少用于后牙.     

Composite resin veneers: a new technique.

A new technique for the fabrication of composite resin direct veneers is presented. In this technique, a transparent acrylic resin matrix is fabricated before preparation of the facial surface of the tooth, to allow the adequate reproduction of contour, shape, and surface texture originally exhibited by the tooth. Advantages, as well as limitations, of the procedure are also presented.     

The effect of a vital bleaching technique on enamel surface morphology and the bonding of composite resin to enamel

summary This study examined the effect of a nightguard vital bleaching procedure on enamel surface morphology and the shear bond strength of a composite resin luting cement to enamel. Extracted human teeth were bleached for 1 week using a vital bleaching product. Control teeth were brushed with a fluoride toothpaste and processed similarly to the bleached teeth, however the bleaching product was substituted with artificial saliva in the night guards. Teeth were stored in artificial saliva for 24 h, 1, 6 or 12 weeks and then examined for any surface changes using light and scanning electron microscopy. The effect of etching surfaces with 37% phosphoric acid was examined at the scanning electron microscope level. The shear bond strength of composite resin luting cement to both buccal and lingual surfaces of bleached and control teeth was determined. Light microscopy investigation suggested the bleaching process resulted in a loss of mineral from enamel which was evident 24 h after bleaching and was sustained following 12 weeks storage in artificial saliva. Scanning electron microscopy showed a definite change in the surface texture of the bleached enamel surface. Acid etching of the bleached enamel surface produced loss of prismatic form and the enamel appeared overetched. The mean shear bond strength between composite resin luting cement and etched enamel tended to be lower for bleached enamel surfaces, however no significant difference in shear bond strength was noted between control and experimental groups. The results of this study suggest that bleaching resulted in changes to the surface and subsurface layers of enamel. Although surface changes were observed in the etched enamel, the shear bond strength of composite resin luting cement to etched bleached enamel appeared to be clinically acceptable     

Using opaquers under direct composite resin veneers: an illustrated review of the technique

In restorative dentistry direct composite resin materials can be used to conservatively resolve many esthetic problems. Opaque resins are often necessary to mask discolorations and/or dark backgrounds when restoring anterior teeth. This article presents a direct composite resin veneer technique using opaquers. Potential problems with the tone of restorations after the use of opaquers are discussed. Advantages, limitations, and the clinical technique are presented. Training, as well as attention to the technique, contributes to an acceptable result.
CLINICAL SIGNIFICANCE
Resinous opaquers can be used as a valid adjunct to the direct composite resin veneer technique when conservatively restoring dark teeth.